Bed frame



FIG. 1 is a front elevation view of a bed frame showing our new design;

FIG. 2 is a front perspective view thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a right side elevation view.

Views of the bed frame not shown in the figures form no part of the claimed design. The dashed broken lines illustrating portions of the bed frame and the mattress are for environmental purposes only and form no part of the claimed design. 

CLAIM The ornamental design for a bed frame, as shown and described. 